This dialog appears when you have chosen to provide your own (‘User-Defined’) cost model for estimating the purchase cost of a specific equipment utilized by a unit procedure in a process. This option is part of the ‘Purchase Cost tab’ of the Equipment Data dialog, see Equipment Data Dialog: Purchase Cost Tab.
For more details about the user-defined cost model (UDCM), see The User-Defined Cost Model (UDCM).
•Reference Year
When specifying cost model, you must specify the year at which the model’s predictions are accurate. If the year of analysis happens to be a future year, the application will update the cost using the Chemical Engineering Index.
•Model Parameters (Qo, Co, a)
Since often there isn’t a single triplet of (Qo, Co, a) to adequately predict the cost over the entire range of size, it may be more appropriate to break up the range of sizes into smaller regions and provide a triplet for each interval region. You can use the buttons right over the top-right end of the table to add 
, insert 
or delete 
a new region.
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The size variable depends on the type of equipment resource that is hosting the procedure and it cannot be modified by the user. For example, for vessels, the size variable is ‘Volume’, for heat exchangers, the size variable is ‘Heat Transfer Area’, and so on. Furthermore, care should be taken to provide the model parameters (Qo, Co and a) in such units that the prediction is made when size is employed by the model in SI units. |
Each range of capacity must have its upper limit be higher than the lower limit. For two consecutive ranges, the lower limit of the higher range must be the same as the upper limit of the next. This way, no overlaps and no gaps are generated in the size range. The entire range of capacity must be large enough to include:
● The current, user-specified size (capacity) of the equipment, if it’s in ‘Rating Mode’
● The soon-to-be-calculated size (capacity) of the equipment, if it’s in ‘Design Mode’; since in ‘Design Mode’ the program will only allow sizes to go up as high as the user-set max value for the capacity (size) of that equipment type (e.g. “Max Volume” for vessels, “Max Area” for filters, etc.), it is important that UDCMs must have their set intervals to include this upper value of capacity.
•Local / Database cost models
Cost models can be either introduced locally (for the needs of the process model at hand) hence the “Use locally defined cost model” radio button, or they can be imported from the database by selecting the “Use cost model from database” radio button. Once clicking on the latter you will be presented with User-Defined Cost Model Select Dialog where you can select a UDCM from the collection stored in your SuperPro (User) DB to import. The user-defined cost model dialog now will also show the name of the UDCM imported from the database and also the “Import” button which you can use to change your database UDCM selection (see the following screen).
Locally-defined cost models can also be deposited in the SuperPro (User) DB by clicking on the Deposit/Update User Cost Model in DB button 
. The User-Defined Cost Model Select Dialog will appear where you may specify a new name for the deposited UDCM or just select an existing UDCM from the list to update its values.
